\begin{table}[htbp]\centering
\def\sym#1{\ifmmode^{#1}\else\(^{#1}\)\fi}
\caption{Effects on quitting smoking in the counterfactual experiments \label{cfreg:quitter}}
\begin{tabular}{l*{2}{c}}
\hline\hline
                &\multicolumn{1}{c}{(1)}         &\multicolumn{1}{c}{(2)}         \\
\hline
Cognitive ability&    0.022\sym{***}&    0.080\sym{***}\\
                &  (0.007)         &  (0.004)         \\
Non-cognitive ability&    0.345\sym{***}&    0.169\sym{***}\\
                &  (0.013)         &  (0.008)         \\
\hline
Observations    &   11,786         &   11,786         \\
Pseudo R2       &    0.304         &    0.081         \\
\hline\hline
\multicolumn{3}{l}{\footnotesize Marginal effects; Standard errors in parentheses}\\
\multicolumn{3}{l}{\footnotesize  (d) for discrete change of dummy variable from 0 to 1}\\
\multicolumn{3}{l}{\footnotesize \sym{*} \(p<0.10\), \sym{**} \(p<0.05\), \sym{***} \(p<0.01\)}\\
\end{tabular}
\end{table}
